Combination earth augers and underreamers



May 1953 c. D. RAWLINSON, SR 2,836,396

COMBINATION EARTH AUGERS AND UNDERREAMERS Filed April 5, 1956 Fig. 2

Char/es 0 Raw/inson, Sr.

IN VEN TORv BY MM 25% United States. Patent COMBINATION EARTH AUGERS AND UNDERREAMERS Charles D. Rawlinson, Sn, Dallas, Tex.

Application April 5, 1956, Serial No. 576,383

2 Claims. (Cl. 255-69) My invention relates to improvements in earth angers and underreamers of the general type forming the subject matter of my U. S. Patent No. 2,481,781, dated September 13, 1949 and in which an underreamer blade is pivotally mounted for projection outwardly of an anger from a retracted inoperative position into an operative position to underream the bottom of a hole bored by the auger.

The primary object of my invention is to provide for vertically slidingly mounting the anger on an operating Kelly bar of a drill rig for operation thereby and for projection and retraction of the underreamer blade in response to relative vertical movement of the auger and Kelly bar, all in a manner such that the underreamer blade will be retracted at the beginning of and during a boring operation and may be projected at will at the bottom of the bored hole'by operation of the Kelly bar.

Another object is to provide means on the auger for carrying earth away from the underreamer blade above and around the same so as to prevent it from being clogged and frozen in inoperative position.

Other and ancillary objects, together with the precise nature of my improvements, will be readily understood when the following description and claims are read with reference to the accompanying drawing in which:

Figure l is a view in perspective, partly broken away and illustrating a combined auger and reamer embodying my improvements;

Figure 2 is a view in perspective of the same rotated through an angle of 180;

Figure 3 is a fragmentary view in vertical longitudinal section taken on the line 33 of Figure 1;

Figure 4 is a view in horizontal section taken on the line 4--4 of Figure l; and

Figure 5 is a fragmentary view in perspective of a modified embodiment of the invention.

Referring to the drawing by numerals, the type of anger and underreamer with which my improvements are concerned comprises a vertically elongated hollow shank 3 which is of rectangular cross section. The shank 3 is provided at its upper end with a reinforcing flange 9 and at its lower end with an axial pilot spud 11.

A circular, horizontal guide plate 13 is formed on the lower end of the shank 3 and which is provided with a pair of substantially diametrically opposite, V- shaped radial slots 15, 17, and with a downturned lip 19 at one side of the slot to which an auger cutting blade 21 is bolted, as at 23, to incline downwardly in substantially radial position relative to the spud 11.

The underreamer blade 25 extends vertically alongside the shank 3 at a right angle to the cutter blade 21 and in vertical alignment with the slot 17 and comprises a reduced upper arm 27. The underreamer blade 25 is vertically swingably mounted for projection and retraction, relative to the shank 3, by means of a vertically swingable link 29 pivoted at its opposite ends to the spud 11 and to the lower end of said blade 25, at

,EQQ

31, 33, respectively, said means further including a vertically swingable upright second link 35 pivoted at its lower end, as at 37, to the upper end of the arm 27 and having its upper end pivoted on a cross bolt 39 vertically slidable in longitudinal vertical slots 41 on opposite sides of the shank 3. A retaining nut 43 is provided on the cross bolt 39.

As will be clear, the described mounting means for the underreamer blade 25 provides for upward and downward sliding of the cross bolt 39 in the shank 3, and downward sliding of said cross bolt will cause the underreamer blade 25 to swing downwardly and outwardly of the shank 3 into projected, operative position in which it projects past the edge of the guide plate 13 with the link 29 in the slot 17, whereas, upward sliding of the cross bolt 39 will cause said underreamer blade 25 to swing upwardly and inwardly of the shank 3 into vertical, retracted, inoperative position in which it is disposed inwardly of the edge of the guide plate 13.

According to my improvements, the shank 3 is vertically, slidably sleeved onto the lower end of an operating Kelly bar 45, of rectangular cross section, such as is used in the ordinary drill rig, not shown, and the shank 3 is slightly larger internally in cross section than the Kelly bar 45 for limited relative rotation of said shank 3 and Kelly bar 45. The shank 3 is closed at its lower end, as at 47, to limit relative sliding of the Kelly bar 45 downwardly in said shank, and the spud 11 is formed integrally on the lower end of said shank 3.

The cross bolt 39 extends through the Kelly bar 4,5 for vertical movement therewith. A helical auger blade 49 is provided on the shank 3 and which spirals upwardly from the juncture of the lip 19 with the guide plate 13 and is provided with a slot 51 therein receiving the arm 27 and link 35. A vertical lateral stop flange 53 is provided on the shank 3 between convolutions of the auger blade 49 and which lies behind the link 35 and the underreamer blade 25 in boring and underreaming.

Referring now to the operation, the shank 3 normally slides downwardly on the Kelly bar 45 so that the cross bolt 39 is slid upwardly in the slots 41 against the upperend hereof and the underreamer blade 25 is retracted, as shown in broken lines in Figure 1, with both the link 35 and the underreamer blade 25 backed by the stop flange 53. When a hole is started, and the spud 11 strikes the ground, the Kelly bar 45 rotates slightly in the shank 3 before picking up the shank and thereby binds against the cross bolt and binds said bolt against the sides of the slots 41 thereby holding the underreamer blade 25 retracted at the start of and during boring. When operation of the underreamer blade 25 is desired, rotation of the Kelly bar 45 is stopped and said bar 45 is down crowded in the shank 3 to slide the same downwardly into the shank thereby sliding the cross bolt 39 downwardly in the slots 41 to project the underreamer blade 25 as shown in full lines in Figure l. Downward sliding of the Kelly bar 45 in the shank 3 is limited by engagement of said bar with the lower end 47 of the shank 3. When the underreamer blade 25 is projected, the flange 53 prevents the link 35 from swinging rearwardly on the cross bolt 39 to hold said blade 25 projected in opposition to pressure thereagainst. The underreamer blade 25 is retracted, after under-reaming, by raising the Kelly bar 45 to slide the cross bolt 39 upwardly in the slots 41. The auger blade 49 feeds the earth upwardly away from the underreamer blade 25 before and during underreaming to prevent clogging of said blade.

In the modified embodiment shown in Figure 5, the upper 55 of the underreamer blade 57 may be pivoted directly on the cross bolt 59 when shorter shanks 61 an'djanger blades 63 are utilized.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changeswill'rreadily ,occur to. .thosei skilledi'in the art,tit is not desired to limit thelinvention" tolthe; exact construction: and operation shown and describe-chi and; accordingly, "all' suitable modifications and equivalents, may be resorted to, falling withinthe scope of the invention as claimed. f a 7 t What is claimed as new is asiollowsr; a V 1. In a combined earth augerandunderreamer, a rotatable vertically movable drivingwbar, 'a vhollow shank slidably sleeved onto the, lower end of said. bar andv rotatable thereby, a, pilot fspud' onthe lowerend'of said shank, said shank being slidabie downwardly on said bar'under the infiucncerof gravity, said bar being slidable downwardly in said shank, anunderreamer blade, means pivotally mounting said blade on said spud forprojection-and retraction relative to said shank into operative and inoperative positions respectively;rneans pivotally connecting said blade tosaid bar for retraction intrer sponse to downwardslidingof said shank and projection in response to downward sliding of said bar, ahelical blade on said-shank for displacing earth upwardly away from rsaidtfirst named blade topre vent clogging thereof, said second named means comprising. a link pivoted to said blade and; to said banand a flange-on said sh ank" backing saidlink to preventpivoting of the link on said blade when 'sajidrblade' is projected.

2. A combination augerand underreamer comprising fastener means rigid with said bar and extending through 3 said slot for limiting relative sliding movement and relative rotation between the bar and shank, said shank havinga radial jblade mounted on saidqshanl; adjacent the, bottom end thereof, said blade being inclined, downwardly for boring a hole in earth and causing initial axial movement ofthe earth, a spiral conveyor auger rigid with the shank for moving the earth axially of the shank, said' conveyor auger extending substantially throughout the length of the shank, an axial pilot spud,

on the lower end of said shank, an underreainer blade;

- a vertically disposed drive bar capable of vertical move- 7 4" a disposed vertically and movable 7 from" an inoperative position disposed within the confines toffthe radial blade;

to 'an operative position projecting outwardly of the w radial blade for underreaming the bored hole upon rotation of the shank with the unclerreamer blade in operative position, an interconnecting link disposed between the lower end'of the underreamer blade and the shank for swinging the underre amer blade outwardly upon downward movement of theunderreamerblade, the upper" and of the nnderreamer blade being pivotall'y' supported ironl said fastening means for movement with'said driv- 7 ing bar, an: outwardly projecting vertical flange on the shank limiting. movement of the underreamer :blade' towards the inoperative position, said linkbeing in upwardly and outwardly inclined relation .when'the'underreamer bid: is in inoperative position for swinging the, lower end of, the underreamer blade outwardly'when 'the bar and fastening means are moved downwardly, the" weight of the-shank retaining-the underr'eamer ;blade'iniinop-' crativezp'osition whengitlieshankis suspended from the bar and'whencthe downwardly inclined radial blade-v and auger pull-the shank downwardly in the earth at a'speed a at least equal to the d'owriward'nlovement of the .driv-J Lag bar with :the frictional engagementbetweenrthe fas tenin'grmeans and one edge of the-barinfrelation Itol the shank when transmittingQtorque from the drivingebai' m2 7 the shank during the normal drilling operation, said T 'underreamer blade being moved tot'an. operative posi; tion byidownwardtmovement of the'driving bar: in rela- 'l tion .to;the shank after" the .hole 'has' been bored and the"- bar is notirotating thus permitting free sliding movementbetween the bar and shank for moving the upper 'end of the'underreamerblade downwardly and causing-the lower end to swing. outwardly beyond the outer end, of the radial blade for underreaming the hole. '7

References Cited in the file of this patent i 7 i umrno's'rArnsiAraNrs 1 Douglass Q Mar. 27-, 1883 r 1,235,569 j Jennings Aug. 7, '19'17! 1,285,347 Otto N0v. l-9, 19718 5 1,737,960 Cramer ....'.'..V... Dec. 3,1929 1 '2,48l,78l 'Rawlinson Sept."13,' 1949 

